Slash Internals

The Result Object

Running tests store their results in slash.core.result.Result objects, accessible through slash.context.result.

In normal scenarios, tests are not supposed to directly interact with result objects, but in some cases it may come in handy.

A specific example of such cases is adding additional test details using details`. These details are later displayed in the summary and other integrations:

def test_something(microwave):
    slash.context.result.details.set('microwave_version', microwave.get_version())

See also


The Session Object

Tests are always run in a context, called a session. A session is used to identify the test execution process, giving it a unique id and collecting the entire state of the run.

The Session represents the current test execution session, and contains the various state elements needed to maintain it. Since sessions also contain test results and statuses, trying to run tests without an active session will fail.

The currently active session is accessible through slash.session:

from slash import session

print("The current session id is",


Normally, you don’t have to create slash sessions programmatically. Slash creates them for you when running tests. However, it is always possible to create sessions in an interpreter:

from slash import Session

with slash.Session() as s:
     ... # <--- in this context, s is the active session

Test Metadata

Each test being run contains the __slash__ attribute, meant to store metadata about the test being run. The attribute is an instance of slash.core.metadata.Metadata.


Slash does not save the actual test instance being run. This is important because in most cases dead tests contain reference to whole object graphs that need to be released to conserve memory. The only thing that is saved is the test metadata structure.

Test ID

Each test has a unique ID derived from the session id and the ordinal number of the test being run. This is saved as and can be used (through property) as